1. Field of the Invention
The present invention relates to lighting systems. More specifically, the present invention relates to the process of automatically calibrating a lighting control system that facilitates daylight-harvesting.
2. Related Art
Most commercial spaces with windows receive enough daylight to at least partially reduce the need for electric lighting. Daylight-harvesting systems strive to reduce the amount of electric lighting used when there is sufficient daylight present. For instance, a daylight-harvesting system can dim or switch electric lights to complement the amount of available daylight. Reducing electric lighting based on the availability of daylight can provide significant energy savings and can reduce peak energy demand.
However, installing and maintaining daylight-harvesting systems can involve substantial expense and effort. For instance, daylight-harvesting systems can involve substantial “commissioning,” i.e., adjusting for the local environment and verifying that the system is (and remains) calibrated and functional. For instance, the control system for a daylight-harvesting system may originally be calibrated by a human technician upon installation, but lose calibration over time due to changes in the area being illuminated and/or aging of the lighting system. Ongoing manual calibration can involve considerable expense, while an uncalibrated lighting system may operate improperly, and can potentially lead to user annoyance and system disablement, with a resulting loss of energy savings.
Hence, what is needed is a method and an apparatus for improving lighting control for daylight-harvesting systems.